Fabrics containing a filler and methods of enhancing crop growth

ABSTRACT

Fabrics suitable for a wide variety of uses, including coverage of crops, crop planting sites, or both, are disclosed. The fabrics may comprise at least one spunbond layer comprising filaments including a filler. The at least one spunbond layer may comprise a basis weight of least about 12 grams-per-meter-squared and the at least one spunbond layer may comprise an average transmittance value within the photosynthetic active radiation (PAR) across wavelengths 400 nm to 700 nm comprising about 37% or less. Methods of enhancing crop growth are also disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.15/015,987 filed Feb. 4, 2016, which claims priority to U.S. ProvisionalPatent Application No. 62/111,972 filed Feb. 4, 2015, and claims thebenefit of the its earlier filing date under 35 U.S.C. 119(e); each ofU.S. patent application Ser. No. 15/015,987 and U.S. Provisional PatentApplication No. 62/111,972 are incorporated herein by reference in theirentirety.

TECHNICAL FIELD

The presently-disclosed invention relates generally to fabrics includingat least one filler material therein. The fabrics may be utilized toenhance crop growth at a crop planting site.

BACKGROUND

Crop covers have been used commercially in the agriculture field toenhance plant growth for decades. Materials for crop covers, such asfilms, nonwovens, or woven materials, may be placed above a cropplanting site to protect the site from birds, insects, rain, hail, windand excessive sun. For example, woven or film crop covers are used inthe agriculture field for a variety of purposes, such as weedsuppression and soil retention.

In some instances, thermal nonwovens are utilized as crop covers whichare designed to let rain and irrigation through, while holding in heat.Accordingly, such nonwovens can typically be utilized to preventfreezing of a crop or plant to extend growing and/or selling seasons.

There at least remains a need, however, in the art for a cost-effective,high performance nonwoven fabric suitable for crop coverage applicationsfor improving yield in a variety of climates.

BRIEF SUMMARY

One or more embodiments of the invention may address one or more of theaforementioned problems. Certain embodiments of the invention, forexample, provide nonwoven fabrics containing at least one fillertherein. For instance, certain embodiments of the invention comprise afabric including at least one spunbond layer (e.g., having a thicknessfrom about 3 mils to about 10 mils) comprising a plurality of filaments.In at least a portion (or all) of the filaments of the at least onespunbond layer include one or more fillers therein. In certainembodiments of the invention, the one or more fillers may be completelycontained (e.g., the filler does not protrude from the sides of thefilaments) within the filaments. In certain other embodiments of theinvention, however, the one or more fillers may at least partiallyprotrude from the sides of the filaments. The at least one spunbondlayer may comprise a variety of basis weights. In certain embodiments ofthe invention, for example, the fabric may comprise a basis weight ofleast about 12 grams-per-meter-squared (gsm). In accordance with certainembodiments of the invention, an average transmittance within thephotosynthetic active radiation (PAR) value across wavelengths 400 nm to700 nm of the at least one spunbond layer comprises 37% or less (e.g.,between about 25% and 35%). In accordance with certain embodiment of theinvention, the fabric may further comprise an infrared radiation(IR)-transmittance value across wavelengths 7000 nm to 14000 nm of thefabric from about 10% to about 70% (e.g., about 40 to about 60%, about10 to about 30%). In accordance with certain embodiments of theinvention, the spunbond layer of the nonwoven fabric comprises a thermalpoint bonded spunbond. Nonwoven fabrics according to certain embodimentsof the invention may comprises an air permeability of greater than about1200 CFM.

In certain embodiments of the invention, the filaments may comprise fromabout 1 wt % to about 30 wt % of the filler (e.g., from about 3 wt % toabout 25 wt % of the filler, from about 3 wt % to about 15 wt % of thefiller, from about 3 wt % to about 10 wt % of filler). In certainembodiments of the invention, the filler may comprise organic particles,inorganic particles, and/or combinations thereof. In an embodiment ofthe invention, the filler may comprise s a polymer material having amelting point that exceeds the melting point of filaments of thespunbond layer. Additionally or alternatively, the filler may comprise,in accordance with certain embodiments of the invention, calciumcarbonate, clay, talc, and/or any combination thereof. In one embodimentof the invention, the filler comprises an alkaline earth carbonate.

The filler, according to certain embodiments of the invention, maycomprise a coated filler. In certain embodiments, the coated fillercomprises a coating comprising at least one organic material. In anembodiment of the invention, the at least one organic material comprisesone or more fatty acids, salts of fatty acids, esters of fatty acids,and/or any combination thereof. In certain embodiments of the invention,the at least one organic material may comprise stearic acid, stearate,ammonium stearate, calcium stearate and/or any combinations thereof.

Nonwoven fabrics according to certain embodiments of the invention maycomprise one or more fillers, in which the filler may comprise anaverage particle size between about 1 micron to about 10 microns (e.g.,between about 2 micron to about 6 microns).

The plurality of spunbond filaments, according to certain embodiments ofthe invention, may comprise one or more polyolefin polymers. In certainembodiments, the one or more polyolefin polymers comprise polypropylene,polyethylene, or a mixture of both. In an embodiment of the invention,the at least a portion of the spunbond filaments comprise polypropyleneproduced by a metallocene catalyst.

Nonwoven fabrics according to certain embodiments may further include atleast a portion of the spunbond filaments comprise a blend of one ormore polyolefin polymers and at least one elastomer. The spunbondfilaments, in accordance with certain embodiments of the invention,comprise from about 0.1 wt % to about 30 wt % (e.g., including fromabout 0.1 wt % to about 20 wt %) of the at least one elastomer. In anembodiment of the invention, the at least one elastomer comprises apolypropylene-based elastomer comprising isotactic propylene repeatunits and random ethylene units. The isotactic propylene repeat units,in an embodiment of the invention, comprise from about 70% to about 90%of the elastomer. In certain embodiments of the invention, themixture/blend of the one or more polyolefin polymers and the at leastone elastomer comprises a greater quantity of the one or more polyolefinpolymers than the at least one elastomer.

In certain embodiments of the invention, at least a portion of thefilaments of the nonwoven fabrics may comprise an ultravioletstabilizer. In one embodiment of the invention, the nonwoven fabrics maycomprise an ultraviolet coating disposed onto at least one surface ofthe fabric.

In another aspect, certain embodiments of the invention provide a methodof enhancing crop growth. In some embodiments of the invention, themethod may comprise covering a crop planting site with afiller-containing fabric as disclosed herein, in which the crop plantingsite comprises one or more crops planted thereon. In accordance withcertain embodiments of the invention, the step of covering the cropplanting site may comprise directly or indirectly applying thefiller-containing fabric either prior to emergence of the one or morecrops or after emergence of the one or more crops. Methods according tocertain embodiments of the invention may comprise applying the fabricdirectly or indirectly over the crop planting site from between about 24hours to 288 hours after emergence of the one or more crops. In certainembodiments of the invention, the methods may comprise applying thefabric directly or indirectly over the crop planting site from betweenabout 24 hours to 288 hours after planting of the one or more crops.

In accordance with certain embodiments, the method may further comprisemaintaining the fabric directly or indirectly over the top of the cropplanting site for a total time duration comprising from about 200 hoursto about 4400 hours (e.g., about 700-about 1800 hours). In oneembodiment of the invention; the method may further comprise inspectingthe one or more crops prior to expiration of the total time duration,for example, by removing at least a portion of the fabric, viewing theone or more crops, and re-applying the fabric directly or indirectlyover the top of the crop planting site. In accordance with certainembodiments of the invention, the method may further comprise harvestingthe one or more crops. In methods according to certain embodiments ofthe invention, the one or more crops may comprise field crops, cropswithin a greenhouse, and/or crops within a macro-tunnel. In oneembodiment, the one or more crops comprise vegetables. The one or morecrops according to an embodiment of the invention may comprise melons.In one embodiment of the invention, the one or more crops may comprisepotatoes.

BRIEF DESCRIPTION OF THE DRAWING(S)

The invention now will be described more fully hereinafter withreference to the accompanying drawings, in which some, but not allembodiments of the invention are shown. Indeed, this invention may beembodied in many different forms and should not be construed as limitedto the embodiments set forth herein; rather, these embodiments areprovided so that this disclosure will satisfy applicable legalrequirements. Like numbers refer to like elements throughout.

FIGS. 1A-1D illustrate cross-sectional scanning electron microscope(SEM) micrograph views of meltspun filaments including varying amountsof filler comprising calcium carbonate according to certain embodimentsof the invention;

FIG. 2 illustrates a SEM micrograph view of meltspun filaments includingabout 12 wt % (15 wt % masterbatch that is 80% loaded with filler) offiller comprising calcium carbonate according to an exemplary embodimentof the invention;

FIG. 3 illustrates a plot layout for an experimental field study fortesting an embodiment of the inventive nonwoven;

FIGS. 4A-4D illustrate boxplots of surface and soil temperature (notcontrolled for random factors) for different field treatments, at day(06:00-18:00) and night (18:00-06:00), respectively, in which the boxesrepresent the 25-75 quantil range, the solid black line the median andthe whiskers represent 1.5 interquantil range while outliers are markedas dots;

FIG. 5 illustrates photosynthetic active radiation (PAR)-transmittancetest results for a polypropylene spunbond fabric containing fillercomprising calcium carbonate, an exemplary embodiment of the invention,and a standard polypropylene spunbond fabric that is devoid of fillermaterial;

FIG. 6 illustrates a comparison of soil temperature data for afiller-containing fabric, according to certain embodiments of theinvention, a standard fabric (no filler), and a control plot having nocover;

FIG. 7 illustrates the minimum air temperature beneath the fabric versusthe ambient air temperature;

FIG. 8 illustrates the maximum air temperature beneath the fabric versusthe ambient air temperature;

FIGS. 9A and 9B illustrate average air and soil temperatures during thenight-time hours of a field study;

FIGS. 10A and 10B illustrate average air and soil temperatures duringthe day-time hours of a field study;

FIG. 11 illustrates the measured opacity of a spunbond polypropylenehaving varying degrees of calcium carbonate filler therein, according tocertain embodiments of the invention;

FIG. 12 illustrates the measured air permeability (cfm at 125 Pa.) of aspunbond polypropylene having varying degrees of calcium carbonatefiller therein, according to certain embodiments of the invention;

FIGS. 13A-13F illustrate the visual differences in nonwoven fabricshaving varying amounts of filler, according to various embodiments ofthe invention, compared to a nonwoven fabric having no filler; and

FIG. 14 illustrates various mechanical properties for a standardpolypropylene spunbond fabric substantially free of filler and a calciumcarbonate-containing polypropylene spunbond including about 12 wt % (15wt % masterbatch that is 80% loaded with calcium carbonate) of calciumcarbonate according to an embodiment of the invention.

DETAILED DESCRIPTION

The invention now will be described more fully hereinafter withreference to the accompanying drawings, in which some, but not allembodiments of the invention are shown. Indeed, this invention may beembodied in many different forms and should not be construed as limitedto the embodiments set forth herein; rather, these embodiments areprovided so that this disclosure will satisfy applicable legalrequirements. As used in the specification, and in the appended claims,the singular forms “a”, “an”, “the”, include plural referents unless thecontext clearly dictates otherwise.

Certain embodiments of the invention provide a fabric (e.g., a spunbondfabric or fabric comprising a spunbond layer) that includes a fillermaterial dispersed throughout at least a portion of the filamentsforming the fabric. In certain embodiments of the invention, the fabricmay be used as a crop cover for a variety of crops. In this regard,certain embodiments of the invention may provide methods of enhancingcrop growth in which a fabric, in accordance with certain embodiments ofthe invention disclosed herein, may be applied directly or indirectlyover a crop planting site having one or more varieties of crops plantedthereon. Coverage of a crop planting site with certain fabrics disclosedherein may provide one or more agronomical benefits (e.g., increasedyield, earliness, precocity, etc.).

The term “filler”, as used herein, may comprise particles or aggregatesof particles and other forms of materials that can be added to apolymeric blend. According to certain embodiments of the invention, afiller will not substantially chemically interfere with or adverselyaffect the meltspinning of polymeric filaments. Fillers may comprise,for example, particulate inorganic materials such as, for example,calcium carbonate; various kinds of clay, silica, alumina, bariumsulfate, sodium carbonate, talc, magnesium sulfate, titanium dioxide,zeolites, aluminum sulfate, cellulose-type powders, diatomaceous earth;magnesium sulfate; magnesium carbonate, barium carbonate, kaolin, mica,carbon, calcium oxide, magnesium oxide, aluminum hydroxide, glassparticles, and the like, and organic particulate materials such ashigh-melting point polymers (e.g., TEFLON® and KEVLAR® from E.I. DuPontde Nemours and Company), pulp powder, wood powder, cellulosederivatives, chitin and chitin derivatives, and the like. Fillerparticles may additionally include fertilizers, according to certainembodiments of the invention. Filler particles may optionally be coatedwith a compound that may assist with the processing of the fillerparticles. Indeed, according to certain embodiments of the invention,the filler particles may be coated with a carboxylic acid. In anembodiment of the invention, the filler particles may be coated with afatty acid including salts and esters thereof. For example, withoutintending to be limiting, the fatty acid may comprise stearic acidand/or reduced stearic acid, or a larger chain fatty acid, such asbehenic acid (also known as docosanoic acid). Without intending to bebound by theory, coated filler particles may facilitate the free flow ofthe particles (in bulk) and their ease of dispersion into the polymermelt that may be meltspun into filaments.

The terms “polymer” or “polymeric”, as used interchangeably herein, maycomprise homopolymers, copolymers, such as, for example, block, graft,random, and alternating copolymers, terpolymers, etc., and blends andmodifications thereof. Furthermore, unless otherwise specificallylimited, the term “polymer” or “polymeric” shall include all possiblestructural isomers; stereoisomers including, without limitation,geometric isomers, optical isomers or enantiomers; and/or any chiralmolecular configuration of such polymer or polymeric material. Theseconfigurations include, but are not limited to, isotactic, syndiotacic,and atactic configurations of such polymer or polymeric materialincluding any combinations thereof.

The term “polyolefin”, as used herein, may comprise any of a class ofpolymers produced from a simple olefin (e.g., an alkene the generalformula C_(n)H_(2n)) as a monomer. The term “polyolefin”, in someembodiments of the invention, may more specifically comprisepoly-α-olefins. Exemplary polyolefins include, for example,polyethylene, polypropylene, or copolymers thereof.

The terms “elastomer” or “elastomeric”, as used interchangeably herein,may comprise any material that upon application of a biasing force, canstretch to an elongated length of at least 110% or even to 125% of itsrelaxed, original length (i.e., can stretch to at least 10% or even 25%more than its original length), without rupture or breakage. Uponrelease of the applied force, for example, the material may recover atleast 40%, at least 60%, or even at least 80% of its elongation. Incertain embodiments of the invention, the material may recover fromabout 20% to about 100% of its elongation, from about 25% to about 95%of its elongation, from about 30% to about 90% of its elongation, fromabout 40% to about 80% of its elongation, or from about 50% to about 70%of its elongation. For example, a material that has an initial length of100 mm can extend at least to 110 mm, and upon removal of the forcewould retract to a length of 106 mm (e.g., exhibiting a 40% recovery).Exemplary elastomers may include VISTAMAXX™ propylene-based elastomers(commercially available form ExxonMobile), which comprise copolymers ofpropylene and ethylene. VISTAMAXX™ propylene-based elastomers, forexample, comprise isotactic polypropylene microcrystalline regions andrandom amorphous regions.

The terms “nonwoven” and “nonwoven web”, as used herein, may comprise aweb having a structure of individual fibers, filaments, and/or threadsthat are interlaid but not in an identifiable repeating manner as in aknitted or woven fabric. Nonwoven fabrics or webs, according to certainembodiments of the invention, may be formed by any processconventionally known in the art such as, for example, meltblowingprocesses, spunbonding processes, hydroentangling, air-laid, and bondedcarded web processes.

The term “layer”, as used herein, may comprise a generally recognizablecombination of similar material types and/or functions existing in theX-Y plane.

The term “spunbond”, as used herein, may comprise fibers which areformed by extruding molten thermoplastic material as filaments from aplurality of fine, usually circular, capillaries of a spinneret with thediameter of the extruded filaments then being rapidly reduced, thesefilaments forming a web by deposition on a moving belt and subsequentlybonded. Spunbond fibers may generally not be tacky when they aredeposited onto a collecting surface and may be generally continuous.

The term “substantial” may encompass the whole amount as specifiedaccording to certain embodiments of the invention, and largely but notthe whole amount specified according to other embodiments.

The term “meltblown”, as used herein, may comprise fibers formed byextruding a molten thermoplastic material through a plurality of finedie capillaries as molten threads or filaments and subjecting thosethreads or filaments to the effect of a high velocity, usually hot, gas(e.g. air) streams which attenuate the filaments of molten thermoplasticmaterial to reduce their diameter, which may be to microfiber diameter,according to certain embodiments of the invention, According to anembodiment of the invention, for example, the die capillaries may becircular. Thereafter, the meltblown fibers may be carried by the highvelocity gas stream and may be deposited on a collecting surface to forma web of randomly disbursed meltblown fibers. Meltblown fibers maycomprise microfibers which may be continuous or discontinuous and may begenerally tacky when deposited onto a collecting surface.

I. Fabric (e.g., Fabrics that May be Used in Crop Cover)

In one aspect, certain embodiments of the invention provide nonwovenfabrics containing at least one filler therein. For instance, certainembodiments of the invention comprise a fabric including at least onespunbond layer comprising a plurality of filaments. At least a portion,or optionally substantially all according to certain embodiments of theinvention, of the filaments of the at least one spunbond layer includeone or more fillers therein. In certain embodiments of the invention,the one or more fillers may be completely contained (e.g., the fillerdoes not protrude from the sides of the filaments) within the filaments.In certain other embodiments of the invention, however, the one or morefillers may at least partially protrude from the sides of the filaments.The at least one spunbond layer may comprise a variety of basis weights.In certain embodiments of the invention, for example, the fabric maycomprise a basis weight of least, for example, about 12grams-per-meter-squared (gsm). In accordance with certain embodiments ofthe invention, an average transmittance value within the photosyntheticactive radiation (PAR) across wavelengths 400 nm to 700 nm of the atleast one spunbond layer comprises 37% or less.

In accordance with certain embodiments of the invention, the fabricscomprise properties that exhibit desirable thermicity for plant growth.Without intending to be bound by the theory, thermicity depends on abalance between solar radiation (e.g., mainly ultraviolet radiation,visible, and near infrared radiation), which may pass through the fabricand heats up the area underneath the fabric (e.g., a crop cover), andterrestrial radiation. Terrestrial radiation, for instance, is emittedback to the atmosphere in the long infrared (IR) range (e.g., 7000 to14000 nm wavelengths) during the night or evening. Photosynthetic activeradiation (PAR) between 400 and 700 nm are particularly usefulwavelengths for the photosynthesis process of developing plants/crops.In this regard, fabrics according to certain embodiments of theinvention exhibit a beneficial balance between transmittance within thePAR (e.g., light transmission between 400-700 nm) and blocking of IRradiation escaping into the atmosphere. For example, fabrics accordingto certain embodiments of the invention may be at least partiallytransparent into the PAR while generally (or at least partially) opaqueto IR between wavelengths of 7000-14000 nm. According to an embodimentof the invention, both the type, size and concentration of fillermaterial is selected to achieve a favorable transmittance within the PARfrom about 400 nm to about 700 nm while substantially reducing IRradiation.

In certain embodiments of the invention, the fabric may comprise atleast one spunbond layer. Additionally, certain embodiments of theinvention may comprise additional layers formed by other methods ofmanufacturing nonwoven fabrics, such as meltblowing, hydroentangling,air-laying, electro-spinning, and bonded carded web processes, etc. Incertain embodiments of the invention, however, the fabric may compriseonly spunbond layers. In certain exemplary embodiments of the invention,the fabric may comprise or consist of a single spunbond layer. Furtherpursuant to this embodiment of the invention, the fabric may simplycomprise a single spunbond layer alone. In accordance with certainembodiments of the invention, the fabric may comprise the at least onespunbond layer which has been thermal point bonded.

Fabrics in accordance with certain embodiments of the invention, maycomprise a basis weight of least about 5 grams-per-meter-squared (gsm),10 gsm, or 12 gsm. In certain embodiments of the invention, the basisweight of the fabric may comprise at least about any of the following:5, 8, 10, 12, 15, and 17 gsm and/or at most about 40, 35, 30, 25, 20,and 18 wt % (e.g., about 12-17 gsm, 15-20 gsm, etc.). In certainembodiments of the invention, for example, the fabric may comprise orconsist of a single spunbond layer in which the spunbond layer maycomprise a basis weight of least about 5 grams-per-meter-squared (gsm),10 gsm, or 12 gsm. In certain embodiments of the invention, the basisweight of the fabric may comprise at least about any of the following:5, 8, 10, 12, 15, and 17 gsm and/or at most about 40, 35, 30, 25, 20,and 18 wt % (e.g., about 12-17 gsm, 15-20 gsm, etc.).

Fabrics according to certain embodiments of the invention may one ormore layers each, for example, comprising a plurality of filamentshaving one or more polymers, such as one or more polyolefin polymers. Incertain exemplary embodiments of the invention, the spunbond filamentsforming one or more spunbond layers may comprise one or more polyolefinpolymers comprising polypropylene, polyethylene, or a blend of both. Incertain embodiments of the invention, for example, the filaments formingthe spunbond layer may be formed from a single polymer, such aspolypropylene. Further pursuant to this embodiment of the invention, forinstance, the polyolefin polymer may consist of polypropylene. The oneor more polymers utilized for the production of filaments, such as by ameltspinning process, may be formed from a variety of processes. By wayof example only, the polyolefin polymer may comprise polypropyleneproduced by a metallocene-catalyst process.

In certain embodiments of the invention, fabric may comprise a pluralityof filaments comprising a blend of one or more polyolefin polymers andat least one elastomer. Further pursuant to this embodiment of theinvention, the filaments of, for example, the spunbond layer maycomprise from about 0.1 wt % to about 30 wt % of at least one elastomer.As such, the filaments may comprise at least one elastomer from at leastabout any of the following: 0.1, 0.5, 1, 1.5, 2.0, 2.5, and 3 wt %and/or at most about 30, 20, 10, 5, 4, and 3 wt % (e.g., about 0.5-3 wt%, 2-3 wt %, etc.). In this regard, the polymer blend used for formingthe filaments of the fabric may comprise a greater quantity (e.g., amajority) of one or more polyolefin polymers than the one or moreelastomers.

Although the type of elastomer, according to certain embodiments of theinvention, is not particularly limited, certain exemplary embodiments ofthe invention may comprise a polypropylene-based elastomer comprisingisotactic propylene repeat units and random ethylene units. In certainembodiments of the invention, the polypropylene-based elastomer maycomprise isotactic propylene repeat units comprising from about 70% toabout 90% of the elastomer. Such exemplary elastomers may includeVISTAMAXX™ propylene-based elastomers (commercially available formExxonMobile), which comprise copolymers of propylene and ethylene.VISTAMAXX™ propylene-based elastomers, for example, comprise isotacticpolypropylene microcrystalline regions and random amorphous regions.

In accordance with certain embodiments of the invention, the spunbondlayer or layers may comprise filaments comprising an average diameter(or effective average diameter for non-circular filaments) from about 5to about 30 microns. As such, the filaments of the spunbond layer orlayers may comprise from at least about any of the following: 5, 7, 10,15, and 20 microns and/or at most about 30, 25, and 20 wt % (e.g., about7-20 microns, 5-25 microns, etc.).

In accordance with certain embodiments of the invention, the one or moreof the filaments of the spunbond layer or layers may comprise a fillermaterial therein. For example, the filler may comprise particles oraggregates of particles, which will not chemically interfere with oradversely affect the, for example, meltspun filaments. In at least aportion (or all) of the filaments of the spunbond layer or layersinclude one or more fillers therein. In certain embodiments of theinvention, for example, the one or more fillers may be completelycontained (e.g., the filler does not protrude from the sides of thefilaments) within the filaments. In certain other embodiments of theinvention, however, the one or more fillers may at least partiallyprotrude from the sides of the filaments. Further pursuant to thisembodiment of the invention, the filaments may comprise organicparticles, inorganic particles, or a combination of both. In someembodiments of the invention, the filaments may comprise a polymermaterial having a melting point that exceeds the melting point of thepolymer and/or elastomer forming the filaments of the spunbond layer(s).In certain exemplary embodiments of the invention, for instance, thefilaments may comprise calcium carbonate, clay, talc, or any combinationthereof.

In accordance with certain embodiments of the invention, for example,the filler may be formed from particulate inorganic materials such as,for example, calcium carbonate, various kinds of clay, silica, alumina,barium sulfate, sodium carbonate, talc, magnesium sulfate, titaniumdioxide, zeolites, aluminum sulfate, cellulose-type powders,diatomaceous earth, magnesium sulfate, magnesium carbonate, bariumcarbonate, kaolin, mica, carbon, calcium oxide, magnesium oxide,aluminum hydroxide, glass particles, and the like, and organicparticulate materials such as high-melting point polymers (e.g., TEFLON®and KEVLAR® from E.I. DuPont de Nemours and Company), pulp powder, woodpowder, cellulose derivatives, chitin and chitin derivatives, and thelike, or combinations thereof. In such embodiments of the invention, forinstance, the filler may be an alkaline earth carbonate, such as calciumcarbonate. Filler particles may additionally comprise one or morefertilizers, according to certain embodiments of the invention.

In certain embodiments of the invention, the filler may comprise acoated tiller. For instance, the filler may be partially or completelycovered with a coating material. In certain embodiments of theinvention, for example, the coating material may comprise at least oneorganic material. For example, the organic material may comprise one ormore fatty acids, salts of fatty acids, esters of fatty acids, or anycombination thereof. Exemplary and non-limiting organic coatingmaterials stearic acid, stearate, ammonium stearate, calcium stearate orany combinations thereof.

In accordance with certain embodiments of the invention, the filaments(e.g., spunbond filaments) may comprise from about 1 wt % to about 30 wt% of the filler. As such, the filaments may comprise a filler (e.g.,calcium carbonate) weight percent from at least about any of thefollowing: 0.8, 1, 2.5, 3, 4, 5, 5.5, 7, 8, 9.5, 10, 12, and 15 wt %and/or at most about 30, 25, 24, 20, 16, 15, and 12 wt % (e.g., about5-15 wt %, 3-25 wt %, 3-15 wt %, about 3-12 wt %, about 3-10 wt % etc.).

FIGS. 1A-1D illustrate spunbond polypropylene filaments includingvarying amounts of a masterbatch comprising polypropylene and 80 wt % offiller comprising calcium carbonate. FIG. 1A illustrates spunbondpolypropylene filaments including 5 wt % of the masterbatch (i.e., 4 wt% calcium carbonate). FIG. 1B illustrates spunbond polypropylenefilaments including 8 wt % of the masterbatch (i.e., 6.4 wt % calciumcarbonate). FIG. 1C illustrates spunbond polypropylene filamentsincluding 12.5 wt % of the masterbatch (i.e., 10 wt % calciumcarbonate). FIG. 1D illustrates spunbond polypropylene filamentsincluding 15 wt % of the masterbatch (i.e., 12 wt % calcium carbonate atan 80% loading of calcium carbonate in the masterbatch). FIG. 2 alsoillustrates spunbond polypropylene filaments including 15 wt % of themasterbatch (i.e., 12 wt % calcium carbonate at an 80% loading of masterbatch). FIG. 2 illustrates an exemplary embodiment of the invention inwhich at least a portion of the filler protrudes from the outer surfacesof the filaments.

The filler, according to certain embodiments of the invention, maycomprise an average particle size (or agglomeration of particles) fromabout 1 micron to about 10 microns. As such, the filler may comprise anaverage particle size (or agglomeration of particles) from at leastabout any of the following: 1, 2, 3, 4, 5, and 6 microns and/or at mostabout 10, 9, 8, and 7 microns (e.g., about 1-5 microns, 2-6 microns,etc.).

As noted above, fabrics according to certain embodiments of theinvention may be partially transparent to PAR. For instance, exemplaryfabrics may comprise an average PAR-transmittance value (e.g., averagepercentage of light that pass through the fabric across wavelengths 400nm through 700 nm) comprising 40% or less, 37% or less, 35% or less, or33% or less. In this regard, certain embodiments comprise an averagePAR-transmittance value from at least about any of the following: 20,25, 30, and 32% and/or at most about 40, 37, 35, and 33% (e.g., about20-40%, 25-35%, etc.).

In accordance with certain embodiments of the invention, the fabrics maycomprise an infrared radiation (IR)-transmittance value acrosswavelengths 7000 nm to 14000 nm of the fabric comprising from about 10%to about 70%. As such, the fabric may comprise an infrared radiation(IR)-transmittance value across wavelengths 7000 nm to 14000 nm of thefabric comprising from at least about any of the following: 5, 10, 15,20, 25, and 30% and/or at most about 90, 80, 70, 60, 50, 40, and 30%(e.g., about 40-60%, 10-30%, etc.).

The thickness of the fabrics according to certain embodiments of theinvention may comprise from about 1 to about 20 mils. In this regard,the thicker fabric may exhibit more robustness (e.g., resistance toabrasion, etc.) and/or blockage of IR across wavelengths 7000 nm to14000 nm. Exemplary fabrics, for instance, may comprise a thicknesscomprising from at least about any of the following: 1, 2, 3, 5, and 10mils and/or at most about 20, 15, 12, and 10 mils (e.g., about 3-10mils, 5-10 mils, etc.

In accordance with certain embodiments of the invention, the fabric mayalso comprise one or more commercially available ultraviolet (UV)stabilizers. In certain embodiments of the invention, for instance, theUV stabilizers may be incorporated into the individual filaments of thefabric by adding the UV stabilizers within the melt that may be meltspunfor formation of the filaments. In this regard, the filaments of thefabric may comprise from about 100 ppm to about 1500 ppm of one or moreUV stabilizers. In certain other embodiments of the invention, thefilaments of the fabric may comprise from about 3000 ppm to about 6000ppm of one or more UV stabilizers Filaments of certain exemplaryembodiments of the invention may comprise one or more UV stabilizerscomprising from at least about any of the following: 100, 200, 300, 500,and 600 ppm and/or at most about 1500, 1200, 1000, 800 and 600 ppm(e.g., about 300-800 ppm, 500-600 ppm, etc.). Filaments of certainexemplary embodiments of the invention may comprise one or more UVstabilizers comprising from at least about any of the following: 3000,4000, 5000, and 6000 ppm and/or at most about 4000, 5000, and 6000 ppm(e.g., about 3000-6000 ppm, 3500-5500 ppm, etc.). Additionally oralternatively, the fabric may comprise an ultraviolet coating disposedonto at least one surface of the fabric and/or spunbond layer.

Fabrics according to certain embodiments of the invention may alsocomprise an air permeability comprising at least about 800 CFM, 1000CFM, or 1200 CFM. Exemplary fabrics, for instance, may comprise an airpermeability comprising from at least about any of the following: 800,1000, and 1200 CFM and/or at most about 1500, 1400, 1320, 1300, 1260,and 1250 CFM (e.g., about 1000-1300 CFM, 1200-1260 CFM, etc.).

In another aspect, certain embodiments of the invention of thedisclosure provide methods for forming fabrics disclosed herein. Forexample, an exemplary method may comprise forming a polymeric blend ormelt that is meltspun to form a plurality of filaments. The polymericblend or melt may comprise one or more polyolefin polymers, one or moreelastomers, one or more fillers, and optionally a variety of otheradditives. For instance, the filler material can be added to thepolymeric blend or melt prior and agitated or mixed therein prior tomeltspinning the polymeric blend or melt. In certain exemplaryembodiments of the invention, the polymeric blend or melt may bemeltspun to provide a plurality of filaments and deposited onto a movingbelt to form a web. The formed web may be subsequently bonded, such asby thermal bonding.

II. Methods of Enhancing Crop Growth

In another aspect, certain embodiments of the invention provide a methodof enhancing crop growth. For example, the method may comprise coveringa crop planting site with a fabric, such as a fabric according tocertain embodiments of the invention disclosed herein, in which the cropplanting site comprises one or more crops planted thereon. In accordancewith certain embodiments of the invention, the step of covering the cropplanting site comprises applying the fabric directly or indirectly overthe crop planting site either prior to emergence or after emergence ofthe one or more planted crops. For instance, the fabric may be placeddirectly onto or over a wire-structure located on the crop plantingsites, such that the fabric may not be directly contact the ground orcrops of the crop planting site.

As referenced above, fabrics according to certain embodiments of theinvention for uses in methods disclosed herein may comprise propertiesthat exhibit desirable thermicity for plant growth. For example,thermicity depends on a balance between solar radiation (e.g., mainlyultraviolet radiation, visible, and near infrared radiation), which maypass through the fabric and heats up the area underneath the fabric(e.g., a crop cover), and terrestrial radiation. Terrestrial radiation,for instance, is emitted back to the atmosphere in the long infrared(IR) range (e.g., 7000 to 14000 nm wavelengths) during the night orevening. Photosynthetic active radiation (PAR) between 400 and 700 nm isparticularly useful wavelengths for the photosynthesis process ofdeveloping plants/crops. In this regard, fabrics according to certainembodiments of the invention exhibit a beneficial balance betweentransmittance (e.g., light transmission between 400-700 nm) within thePAR and blocking of IR radiation escaping into the atmosphere. Forexample, fabrics according to certain embodiments of the invention maybe at least partially transparent into PAR while generally (or at leastpartially) opaque to IR between wavelengths of 7000-14000 nm

In accordance with certain embodiments of the invention, the method maycomprise applying the fabric directly or indirectly over the cropplanting site from between about 24 hours to 288 hours after emergenceof the one or more crops. In certain exemplary embodiments of theinvention, the methods may comprise applying the fabric directly orindirectly over the crop planting site at least about any of thefollowing: 24, 48, 72, and 96 hours after emergence of the one or morecrops and/or at most about 288, 250, 200, and 150 hours after emergenceof the one OF more crops.

In accordance with certain other embodiments of the invention, the stepof covering the crop planting site comprises applying the fabricdirectly or indirectly over the crop planting site from between about 24hours to 288 hours after planting of the one or more crops. In certainexemplary embodiments of the invention, the methods may compriseapplying the fabric directly or indirectly over the crop planting siteat least about any of the following: 24, 48, 72, and 96 hours afterplanting of the one or more crops and/or at most about 288, 250, 200,and 150 hours after planting of the one or more crops.

Methods according to certain embodiments of the invention may comprisemaintaining the fabric directly or indirectly over the top of the cropplanting site for a total time duration comprising from about 200 hoursto about 4400 hours, or from about 700 hours to about 1800 hours. Incertain exemplary embodiments of the invention, the methods may comprisemaintaining the fabric directly or indirectly over the top of the cropplanting site for a total time duration comprising from at least aboutany of the following: 100, 200, 400, 700, and 900 hours and/or at mostabout 4400, 3600, 2800, 2200, 2000, 1800, 1500, and 1200 hours. Incertain embodiments of the invention, the methods may further compriseinspecting the one or more crops prior to expiration of the total timeduration. For instance, the step of inspecting the one or more crops maycomprise temporarily removing at least a portion of the fabric, viewingthe one or more crops, and re-applying the fabric directly or indirectlyover the top of the crop planting site. The inspection of the crops mayprovide an opportunity to gauge growth of the crops, disease levels, andgrowth of any unwanted vegetation. In accordance with certainembodiments of the invention, the method may further comprise harvestingthe one or more crops.

In accordance with certain embodiments of the invention, the one or morecrops may comprise a variety of crops/plants. In certain embodiments ofthe invention, for instance, the crops may comprise field crops, cropslocated within a greenhouse, crops located within a macro-tunnelstructure and combinations thereof. Exemplary crops, according tocertain embodiments of the invention, include (but not limited to)vegetables, a variety of melons, peppers, cucumbers, watermelon, leaks,endives, ornamentals, etc.

Methods in accordance with certain embodiments of the invention, mayprovide or comprise an increase in crop yield (e.g., based on drybiomass) as compared to methods using a crop cover (e.g., nonwovenfabric) of the same basis weight and same construction, but being devoidof filler as disclosed herein. In certain embodiments of the invention,the methods may comprise an increase in crop yield e.g., based on drybiomass of at least about any of the following: 3, 5, 8, 10, 12, and 15%increase, and/or at most about 20, 18, and 15% increase (e.g., about5-15%, 10-18%, etc.).

Methods in accordance with certain embodiments of the invention, mayprovide or comprise an increase in earliness (e.g., faster growth) forthe planted crops, which may further provide the option to shorten thevegetation growth cycle, as compared to methods using a crop cover(e.g., nonwoven fabric) of the same basis weight and same construction,but being devoid of filler as disclosed herein. For instance, theearliness of the plant growth may be evaluated by the number of days forthe planted crop to reach a certain size or height of growth. In thisregard, certain embodiments of the invention may provide a difference inearliness from about 1 to about 20 days as compared to methods using acrop cover (e.g., nonwoven fabric) of the same basis weight and sameconstruction, but being devoid of filler as disclosed herein. Forexample, the plant growth associated with the fabric according tocertain embodiments of the invention may grow to the predeterminedgrowth level (e.g., height, weight, etc.) from about 1 to about 20 daysprior to plant growth associated with fabrics of the same basis weightand same construction, but being devoid of filler as disclosed herein.In certain embodiments of the invention, the methods may comprise anincrease in earliness for a given height of emergence of at least aboutany of the following: 1, 3, 5, 10, 15, and 20 days and/or at most about20, 18, 15, and 10 days (e.g., about 3-15 days, 10-20 days, etc.

Examples

The present disclosure is further illustrated by the following examples,which in no way should be construed as being limiting. That is, thespecific features described in the following examples are merelyillustrative and not limiting.

(1) Experimental Field Study

An experimental study was conducted to test how two types of crop coversinfluence temperature and growth of a commercial cultivar of potato,“Gulloye”, in the very northern part of Europe (i.e., Norway). The aimof the experimental study was to illustrate if filler-containing fabricsin accordance with certain embodiments of the present disclosure impactthe growth of crops (e.g., potatoes) in comparison to the use ofcommercially available crop covers. In particular, a filler-containingfabric in accordance with one embodiment of the invention of the presentdisclosure was compared to (i) REICROP® (a polypropylene spunbond fabriccommercially available from Polymer Group, Inc.) and (ii) a control(i.e., a crop planting site without a crop cover). The filler-containingfabric in accordance with one embodiment of the invention and theREICROP® fabric each had a basis weight of 17 gsm.

More specifically, the Norwegian potato cultivar “Gulloye” was used as amodel organism for the experiment. “Gulloye” is a traditional cultivarin northern Norway, known for its quality as a gourmet potato. Theexperimental study took place at the research farm of Bioforsk Nord, inTromso (69°39′11.0″N 18°5440 15.3″E). A Latin square design with threereplicates (blocks) was used to test differences in emergence, maturity,crop yield and dry weight, as well as temperature in soil and air forplots with no cover, REICROP® and a filler-containing fabric. The potatofield was split into nine (9) plots, with each treatment replicated in arandom manner in three blocks (stratified by elevation level). The plotlayout for the experimental study is illustrated in FIG. 3. Thetreatment was categorized as control (no cover), commercial cover type(i.e., REICROP®), and a filler-containing fabric in accordance with oneembodiment of the present disclosure. Each plot consisted of four rowsof six meter plus guard plants. Tubers were planted with asemi-automatic planter with a space of 30 cm between tubers and 72 cmbetween rows.

The tubers where planted on May 27th, just after soil was thawed. Thecrop covers where applied on June 4^(th) and removed on August 15^(th),Only minor amounts of weeds were present in the field, and were manuallyremoved from the field in mid-July. The tubers were harvested onSeptember 1st. In general, disease levels in potato farming in northernNorway are low, and visual inspection did not indicate any differencesamong the treatments with respect to disease level.

Surface temperatures (5 cm above ground) and soil temperatures (5 cmbelow surface) were registered using iButton loggers (Thermochron 8 K40/85C). The logging interval was set to every hour, and a total of57,651 temperatures were logged. The loggers were tested and calibratedfor four days before the start of the experimental study. One of theloggers (ID 2CA positioned above ground, on a REICROP® cover) failedrecording and was replaced 19^(th July.)

After emergence of the plants (about 20 cm height on the best plot),emergence was estimated visually by giving a score ranging from 1-9. Ascore of 1 represents zero plant emergence, and 9 represents an evenplant stand of about 20 cm height.

Crop estimates were obtained by weighing the total crop amount of thetwo middle rows (each of 6 m) in each plot to avoid edge effects. Eachharvested row equaled an area of 4.32 m². Dry matter content wasmeasured using specific gravity (sample weight in air and sample weightin water).

(a) Statistical Analysis

Differences in temperature, emergence and yield for the differenttreatments were tested using general mixed models (function Imer in R).Block was including as random factor to control for random variation doto elevation. As performance of the filler-containing fabric inaccordance with one embodiment of the present disclosure was in focus,this was set as reference level for the contrast analysis. Fortemperature, data was log-transformed to obtain a normal distribution.As emergence score is a discrete measure, Poisson distribution with alog-link was assumed. Differences among treatments were consideredsignificant when their 95% confidence intervals did not overlap zero.All analyses were done in the statistical package R version 3.0.1,library base and Ime4. Differences in temperature variation were testedby Fischer's F-test of variance ratios (function var. test in R).

(b) Temperature Results

Ambient average July temperature was above the overall average measuredat the field station in the period 1995-2013 (15.2° C. vs. 12.16° C.).The covered plots showed increased temperatures compared to the controlas illustrated in Table 1. Above ground temperatures in plots with thefiller-containing fabric in accordance with one embodiment of thepresent disclosure did not differ significantly from the REICROP® cover(0.14.51° C. (95% CI: 14.07-14.98° C.) versus 14.17° C. (95% CI:14.01-14.93° C.). For soil temperatures the pattern was similar; with nosignificant difference in temperatures for the filler-containing fabricin accordance with one embodiment of the present disclosure compared toREICROP®: 13.24° C. (95% CI: 12.85-13.65° C.′ versus 13.47° C. (95% CI:13.06-13.88° C.). This relationship was not altered comparing day(06:00-18:00) and night (18:00-06:00) temperatures as shown in FIGS. 4Aand 4B and in FIGS. 4C and 4D. For air temperatures, there was a smallbut significant higher variation in temperature for thefiller-containing fabric in accordance with one embodiment of thepresent disclosure compared to REICROP® fabric (ratio day time, 95% CI:1.02-1.17, ratio night time, 95% CI: 1.011.17, as shown in Table 1). Themeans and standard deviation of temperatures among the differenttreatments, for soil and air temperatures at day (06:00-18:00) and night(18:00-06:00) times are provide in Table 1. The relative variation(coefficient of variation, CV) of Table 4 is given by standard deviationdivided on mean.

TABLE 1 Standard Parameter Mean Deviation CV Above Surface Temperature,daytime (° C.) Control 14.30 5.68 0.40 New cover type (contains filler)15.76 6.04 0.38 Old cover type (no filler) 15.77 5.76 0.36 Above SurfaceTemperature, nighttime (° C.) Control 11.68 4.60 0.39 New cover type(contains filler) 12.38 4.89 0.39 Old cover type (no filler) 12.31 4.680.38 Soil Temperature, daytime (° C.) Control 12 80 3.19 0.25 New covertype (contains filler) 13.61 2.95 0.22 Old cover type (no filler) 13.762.89 0.21 Soil Temperature, nighttime (° C.) Control 13.40 3.32 0.23 Newcover type (contains filler) 14.07 3.11 0.22 Old cover type (no filler)14.37 3.11 0.22

(c) Modality of Above Ground Biomass

Visual inspection early in the growth season (mid-July) indicateddifferences in emergence between the uncovered versus covered plots,where plots showed higher and more developed plants. There was higheremergence scores for the filler-containing fabric in accordance with oneembodiment of the present disclosure compared to the REICROP® cover: 8(95% CI: 5.21-11.64) versus 7.33 (95% CI: 4.68-10.84). At harvest, therewas no difference in degree of maturity, indicated by percentage ofyellow haulm (less green) for the filler-containing fabric (e.g., newcover type) compared to the standard REICROP® cover (e.g., old covertype): 63.33 (95% CI: 58.02-68.66) versus 63.33 (58.00-68.66) asillustrated in Table 2.

TABLE 2 Response Predictor Estimate SE 95% CI Germination Intercept 2.080.20 (1.65, 2.45) score (1-9) Control −0.69 0.35 (−1.42, −0.01) (n = 9)Old Cover −0.09 0.30 (−0.67, 0.49)  (log Block 0 transformed) (random)Percentage Intercept 63.33 2.89 (58.00, 68.66) Green (%) Control 18.333.60 (11.52, 25.15) (n = 9) Old Cover −1.42 × 10⁻¹⁴ 3.60 (−6.81, 6.81) Block (random) 2.37 Residual 4.41 (random) Crop Size Intercept 16.080.51 (15.13, 17.04) (kg/row) Control 0.22 0.68 (−1.10, 1.53)  (n = 18)Old Cover −2.02 0.68 (−3.33, −0.70) Block 0.28 (random) Residual 1.18(random) Percentage Intercept 25.43 0.43 (24.57, 26.29) dry matterControl −0.63 0.44 (−1.47, 0.21)  (%) Old Cover −0.23 0.44 (−1.07,0.61)  (n = 9) Block 0.52 (random) Residual 0.54 (random)

Table 2 provides the parameter estimates of the influence of differentcover types on emergence of above ground biomass, crop size and drymatter content. The filler-containing fabric was used as reference levelfor the contrast analyses (i.e., differences of other treatmentscompared to new cover). Hence, the effect of the filler-containingfabric is shown by intercept in the table. Germination score is analyzedassuming Poisson distribution and log link, for other responses a normaldistribution and identity link is assumed. Block is included as a randomfactor in the models and estimates for this is given in standarddeviation units.

(d) Crops

The plots covered with the filler-containing fabric had a 2.02 kg(14.4%) higher yield per row than plots covered with the REICROP® cover:16.08% (95% CI: 15.12-17.04%) versus 14.06% (95% CI: 13.10-15.02%)kg/row as shown in Table 2. Comparing the percentage dry matter contentbetween the filler-containing fabric and REICROP® cover revealed nosignificant differences between the treatments: 25.43% (95% CI:24.57-26.29%) versus 25.20% (95% CI: 24.34-26.06%). Estimating yield ofdry matter per row by multiplying crop yield with dry matter content foreach treatment suggests that the filler-containing fabric results inmore dry matter per row (4.09 versus 3.54 kg of dry matter per row).

(e) Discussion

Both cover types increased the temperature both above and below surfaceat the same magnitude. This was reflected by enhanced plant maturationin the covered plots. Interestingly, the experiment showed a higheryield in plots covered of the filler-containing fabric compared to theREICROP® cover. However, although the filler-containing fabric hadincreased yield, the correlation between temperature and yield was lessclear than expected. There was no significant difference in averagetemperature between filler-containing fabric and the REICROP® cover.Likewise, although there was statistically significant more variation intemperature for the filler-containing fabric compared to the REICROP®cover, the magnitude of difference was minor.

A reason for this may be that this summer had an ambient temperaturewell above average the last 20 years. While the high temperatures mayhave been beneficial early in the season, as indicated by differences inemergence between cover plots compared to control, the high mean Julytemperature may actually have been above optimal growth temperatures forthis cultivar. Hence, an earlier removal of the covers or a more rapidgrowing cultivar could have been beneficial for the crop yield.

The REICROP® cover performed significantly worse compared to thefiller-containing fabric as measured by crop yield. When measuring drymatter content, no difference was revealed, excluding differences inwater content as a cause for the difference in yield, measured as mass,of crop. Although the germination scores were slightly higher for thefiller-containing fabric compared to the REICROP® cover, this differencewas not significant. The yield may have been influenced by Julytemperatures well above the average for the last 20 years, influencinggrowth in the main growth period. While lower humidity in the fieldswith the REICROP® cover, either due to higher evaporation rates or lowerpenetration of rain, could have reduced growth of tubers, we are notable to conclude on this as humidity was not measured.

Additionally, the visual inspection of the plants development for allplots when the best plot exhibited 20 cm emergence of the plants toprovide an indication of earliness and precocity. The precocity is thetime gained in a vegetation growth cycle. As noted above, higheremergence scores were exhibited for the filler-containing fabric ascompared to the REICROP® cover: 8 (95% CI: 5.21-11.64) versus 7.33 (95%CI: 4.68-10.84). In this regard, the new cover exhibited improvedearliness for the planted crops. Consequently, the precocity may beimproved according to certain embodiments of the invention. For example,the vegetation growth cycle may be desirably shortened according tocertain embodiments of the invention.

(1) Summary of Experimental Field Study

Both cover types exhibited a clear positive impact on emergence andearly growth, as well as maturation. However, the filler-containingfabric clearly performed significantly better for tuber growth, yieldingin 14.4% higher crop. For dry weight (e.g., the mass of the crops whencompletely dried) this equals an average 15.5% increase in dry matteryield. Moreover, the new type exhibited an improved earliness (e.g.,faster growth) for the planted crops, which may provide the option toshorten the vegetation growth cycle. The study did not reveal anynegative influence of the filler-containing fabric on the plantscompared to the REICROP® cover or control.

(2) Photosynthetic Active Radiation (PAR)-Transmittance

A 17 gsm polypropylene spunbond fabric which included 15 wt %masterbatch having an 80% loading of filler with the balance in apolypropylene resin (total filler composition of about 12 wt %)comprising calcium carbonate, in accordance with certain embodiments ofthe invention, was compared to a standard polypropylene spunbond fabricexcluding any filler material for light transmittance within thephotosynthetic active radiation (PAR) between wavelengths of 400 nm to700 nm. The general shape of both curves were similar, but the calciumcarbonate-containing fabric exhibited a lower value than the fabricexcluding a filler. As illustrated in FIG. 5, the average transmittancevalue within the PAR for the calcium carbonate-containing fabric wasnotably lower than the standard fabric.

Since the rate of photosynthesis is considered to be directly linked tothe transmission in PAR, one would expect plant growth and yield to bereduced when covered with the calcium carbonate-containing fabric. Asillustrated in the preceding section (i.e., “(1) Experimental FieldStudy”), however, the opposite is actually realized according to certainembodiments of the invention. Surprisingly, for instance, use of thecalcium-containing spunbond fabric as outlined in the Experimental FieldStudy above provided an notable increase in yield (e.g., an average15.5% increase in dry matter) and improved earliness and/or precocity.

(3) Field Tests—Temperature Analysis

Additional field tests were performed to compare soil and airtemperatures associated with the use of each of the following: (1) acalcium carbonate-containing spunbond fabric (e.g., 15 wt % ofmasterbatch comprising 80 wt % calcium carbonate); (2) a standardREICROP® spunbond fabric (e.g., devoid of filler); and (3) a control, inwhich no crop covering fabric is utilized. The results are illustratedin FIGS. 6-10. In general, the standard REICROP® fabric provided onaverage, as shown in FIG. 6, a higher temperature value for both soiltemperature (e.g., soil from crop planting site covered by fabric) andair temperature (e.g., air temperature of the air under the fabric). Thedifferences in temperatures were generally small, except for therecorded maximum temperature readings for both the soil temperature (asshown as a bar chart on FIG. 6) and air temperature (shown as a plottedline on FIG. 6). The maximum soil temperature readings for the calciumcontaining-fabric where substantially similar to the control, while theREICROP®) fabric provided a noticeably higher maximum temperature. Asimilar, but less extreme, observation was observed for the maximum airtemperatures.

FIG. 7 illustrates the minimum air temperature (e.g., beneath thefabric) depending on the ambient air temperature. As shown in FIG. 7,the minimum air temperature for both fabrics were similar with nosignificant differences across all recorded ambient air temperatures.FIG. 8 illustrates the maximum air temperature (e.g., beneath thefabric) depending on the ambient air temperature. As shown in FIG. 8,the maximum air temperatures for the REICROP® fabric was noticeablylarger than the maximum air temperatures for the calciumcarbonate-containing fabric for nearly every recorded ambient airtemperature. In this regard, the carbonate-containing fabric provided asimilar thermal protection against extreme drops in air temperaturebelow the fabric, but also mitigated heat “spikes” realized by theREICROP® fabric. The calcium carbonate-containing fabric, for example,provided a reduction in temperature peaks, which may provide anagronomic benefit when ambient air temperatures are above an optimalgrowth temperature for a given crop. FIGS. 9A, 9B, 10A and 10B provide amore detailed representation of average air and soil temperatures duringthe nights of the study (FIGS. 9A and 9B) and during the day (FIGS. 10Aand 10B).

(4) Visual Appearance and Other Properties

Additional studies were performed to illustrate the impact of increasingamounts of filler (e.g., calcium carbonate) on the fabrics opacity andair permeability. FIG. 11 illustrates the measured opacity of a spunbondpolypropylene having varying degrees of calcium carbonate fillertherein. As shown in FIG. 11, which illustrates the opacity (average ofthree points) versus calcium carbonate dosing, the opacity of the fabricwas notably increased with merely about 5 wt % of masterbatch (about 4wt % calcium carbonate) and essentially leveled off at about 8 wt %masterbatch (about 6.4 wt % calcium carbonate).

FIG. 12 illustrates the measured air permeability (cfm at 125 Pa) of aspunbond polypropylene having varying degrees of calcium carbonatefiller therein. As shown in FIG. 12, the air permeability of the fabricwas notably decreased with merely about a 5 wt % of masterbatch (about 4wt % calcium carbonate) and remained significantly reduced until about12.5 wt′%© of master batch (about 10 wt % calcium carbonate).

FIG. 13A illustrates a reference nonwoven fabric substantially free ofany calcium carbonate. FIGS. 13B, 13C, 13D and 13E illustrate the visualdifferences in nonwoven fabrics having 4.0 wt %, 6.4 wt %, 10.0 wt % and12 wt %, respectively, of calcium carbonate. FIG. 13F illustrates anonwoven fabric having about 12 wt % of calcium carbonate but alsoincluding properties that have been adapted over that found in FIG. 13Eto provide a further increase in opacity. For example, without intendingto be limiting, even while the samples represented by FIG. 13E and FIG.13F may have about the same amount of calcium carbonate, the spun sampleleading to the nonwoven fabric of FIG. 13F may be such that the tensilestrength is reduced relative to the sample of FIG. 13E, but yetproviding an improvement in the opacity as shown in the exemplaryembodiment of FIG. 13F in comparison to the exemplary embodiment of FIG.13E.

FIG. 14 illustrates various mechanical properties for a standardpolypropylene spunbond fabric (e.g., devoid of filler) and a calciumcarbonate-containing polypropylene spunbond including 15 wt % of amasterbatch comprising calcium carbonate at an 80% loading effectivelyyielding 12 wt % of calcium carbonate. FIG. 14, for instance, provides acomparison between calcium carbonate-containing polypropylene spunbondfabrics (i.e., referenced as Step 2.1, 3, and 3B in FIG. 14) inaccordance with an embodiment of the invention and the average valuesfor REICROP® L1 product (i.e., referenced as Avg. February-2014 in FIG.14). The abbreviations used in FIG. 14 and corresponding test methodsidentified in Tables 4 and 5 below are summarized in Table 3,

TABLE 3 Full Basis of Abbreviation Nomenclature Measured Value TestMethod BW Basis Weight GSM WSP 130.1(09) MDT Tensile Strength N/50 mmWSP 110.4(09) at Peak Machine Direction MDE Elongation at % WSP110.4(09) Peak Machine Direction CDT Tensile Strength N/50 mm WSP110.4(09) at Peak Cross-Direction CDE Elongation % WSP 110.4(09) at PeakCross-Direction

Table 4 provides the numerical results for the tests identified in Table3, while Table 5 provides the relative values versus the values for thereference sample of Table 4.

TABLE 4 MD CD Sample BW MDT MDE CDT CDE Energy Energy Avg — 24.5 13219.2 138 32 26 February 2014 Reference(100) 16.9 24.4 102 17.8 114 25 20Step 2.1 17.4 26.0 162 16.3 149 42 24 Step 3 17.1 27.1 159 17.1 169 4329 Step 3B 18.3 24.9 170 18.3 199 42 36

TABLE 5 MD CD Sample BW MDT MDE CDT CDE Energy Energy Avg — 100 130 108121 130 130 February 2014 Reference(100) 100 100 100 100 100 100 100Step 2.1 103 106 159 92 131 170 120 Step 3 101 111 156 96 148 174 142Step 3B 108 102 167 103 174 171 179

As shown in FIG. 14 and Tables 4 and 5, the calcium carbonate-containingfabric exhibited improved MDE and a significant elongation increase thatdrives into greater than 50% enhanced energy in the machine direction.Furthermore, there is a slight improvement in tensile strength in themachine direction, and a slight reduction in the tensile strength in thecross-direction.

These and other modifications and variations to the invention may bepracticed by those of ordinary skill in the art without departing fromthe spirit and scope of the invention, which is more particularly setforth in the appended claims. In addition, it should be understood thataspects of the various embodiments may be interchanged in whole or inpart. Furthermore, those of ordinary skill in the art will appreciatethat the foregoing description is by way of example only, and it is notintended to limit the invention as further described in such appendedclaims. Therefore, the spirit and scope of the appended claims shouldnot be limited to the exemplary description of the versions containedherein.

That which is claimed:
 1. A method of enhancing crop growth, comprising:covering a crop planting site comprising one or more crops plantedthereon with a fabric having a spunbond layer comprising filamentsincluding a filler; wherein the fabric comprises a basis weight of leastabout 12 grams-per-meter-squared (gsm); wherein (i) an averagetransmittance value within a photosynthetic active radiation (PAR)across wavelengths 400 nm to 700 nm of the spunbond layer comprises 37%or less, and (ii) an infrared radiation (IR)-transmittance value acrosswavelengths 7000 nm to 14000 nm of the fabric comprises from about 10%to about 70%.
 2. The method of claim 1, wherein covering the cropplanting site comprises applying the fabric directly or indirectly overthe crop planting site prior to emergence of the one or more crops. 3.The method of claim 1, wherein covering the crop planting site comprisesapplying the fabric directly or indirectly over the crop planting siteafter emergence of the one or more crops.
 4. The method of claim 1,wherein covering the crop planting site comprises applying the fabricdirectly or indirectly over the crop planting site from between about 24hours to 288 hours after an emergence of the one or more crops.
 5. Themethod of claim 1, wherein covering the crop planting site comprisesapplying the fabric directly or indirectly over the crop planting sitefrom between about 24 hours to 288 hours after planting of the one ormore crops.
 6. The method of claim 1, wherein the filaments comprisefrom about 3 wt. % to about 10 wt. % of the filler.
 7. The method ofclaim 1, wherein the filler comprises organic particles, inorganicparticles, or combinations thereof.
 8. The method of claim 1, whereinthe filler comprises a polymer material having a first melting pointthat exceeds a second melting point of filaments of the spunbond layer.9. The method of claim 1, wherein the filler comprises a coated filler.10. The method of claim 9, wherein the coated filler comprises a coatingcomprising at least one organic material comprising one or more fattyacids, salts of fatty acids, esters of fatty acids, or any combinationthereof.
 11. The method of claim 9, wherein filler comprises stearicacid, stearate, ammonium stearate, calcium stearate or any combinationsthereof.
 12. The method of claim 1, wherein the filler comprises anaverage particle size between about 2 microns to about 6 microns. 13.The method of claim 1, wherein the fabric comprises an air permeabilityof greater than about 1200 CFM.
 14. The method of claim 1, wherein thespunbond layer comprises a thickness from about 3 mils to about 10 mils.15. The method of claim 1, wherein the filaments comprise a blend of theone or more polyolefin polymers and at least one elastomer.
 16. Themethod of claim 1, wherein the filaments comprise from about 0.1 wt % toabout 20 wt % of the at least one elastomer.
 17. The method of claim 15,wherein the at least one elastomer comprises a polypropylene-basedelastomer comprising isotactic propylene repeat units and randomethylene units.
 18. The method of claim 17, wherein the isotacticpropylene repeat units comprise from about 70% to about 90% of theelastomer.
 19. The method of claim 1, wherein in the filaments comprisean ultraviolet stabilizer.
 20. A method of enhancing crop growth,comprising: (i) covering a crop planting site comprising one or morecrops planted thereon with a fabric having a spunbond layer comprisingfilaments including a filler; wherein (i) an average transmittance valuewithin a photosynthetic active radiation (PAR) across wavelengths 400 nmto 700 nm of the spunbond layer comprises 37% or less, and (ii) aninfrared radiation (IR)-transmittance value across wavelengths 7000 nmto 14000 nm of the fabric comprises from about 10% to about 70%; and(ii) maintaining the fabric directly or indirectly over the cropplanting site for a total time duration of from about 100 to about 4400hours.